Effect of vitamin D3 treatment on glucose metabolism and menstrual frequency in polycystic ovary syndrome women: a pilot study

Effect of vitamin D supplementation on hormones and menstrual cycle regularization in polycystic ovary syndrome women: A systemic review and meta-analysis

AIM

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disease among women of childbearing age. Women with PCOS frequently experience reproductive complications, which are closely associated with the concentration of vitamin D. This systemic review and meta-analysis were conducted to elucidate the possible effect of vitamin D supplementation in PCOS women on hormones, including Luteinizing hormone (LH), follicle-stimulating hormone (FSH), the ratio of LH and FSH (LH/FSH), and the menstrual cycle regularization.

METHODS

We searched PubMed, Web of Science, Ovid MEDLINE, Cochrane Library, and EMBASE for the relevant articles published up to January 2022. The pooled estimates were calculated using RevMan 5.4 software.

RESULTS

Twelve studies involving 849 PCOS patients were included. Our study indicated that vitamin D supplementation could reduce serum LH (standard mean difference [SMD]: -0.41; 95% confidence interval [CI]: -0.54, -0.28; p < 0.01). Subgroup analysis identified that the supplementation of vitamin D ≤4000 IU/day (SMD: -0.69; 95% CI: -1.15, -0.23; p < 0.01), treatment time ≤8 weeks (SMD: -0.61; 95% CI: -0.95, -0.26; p < 0.01), and vitamin D co-supplementation (SMD: -0.37; 95% CI: -0.65, -0.10; p < 0.01) were related to reduce serum LH level. In addition, vitamin D supplementation improved the regularity of menstrual cycle significantly (risk ratio [RR]: 1.35; 95% CI: 1.18, 1.54; p < 0.01). In stratified analysis, the significant effects only existed in dosage of vitamin D >4000 IU (RR: 1.62; 95% CI: 1.02, 2.57; p < 0.01), treatment time >8 weeks (RR: 1.41; 95% CI: 1.06, 1.87; p = 0.02) and vitamin D co-supplementation (RR: 1.18; 95% CI: 1.03, 1.35; p = 0.02). However, vitamin D might have no effects on serum FSH (SMD: -0.05; 95% CI: -0.42, 0.32; p = 0.79) and LH/FSH (SMD: -0.24; 95% CI: -0.55, 0.08; p = 0.14) in PCOS patients.

CONCLUSIONS

Evidence from the existing randomized controlled trials indicated that vitamin D supplementation might improve the LH level and the menstrual cycle regularization but did not have any effect on FSH and LH/FSH levels in PCOS patients.

Effect of calcium and vitamin D supplementation on the clinical, hormonal, and metabolic profile in non-obese women with polycystic ovary syndrome

BACKGROUND

In this study, we investigated the effect of calcium and vitamin D (Ca/Vit D) supplementation on the clinical, hormonal, and metabolic profile of patients with low vitamin D levels. In addition, we investigated the effect of Ca/Vit D supplementation on asymmetric dimethylarginine (ADMA) level in patients with polycystic ovary syndrome (PCOS).

METHODS

In total, 75 patients aged 19-35 years, with a normal body mass index and a diagnosis of PCOS and Vit D deficiency/insufficiency, were included in the study. Patients received 50,000 IU of vitamin D3 once a week for 8 weeks. Afterward, 2500 mg calcium carbonate equivalent to 1000 mg calcium ion and 9.68 mg cholecalciferol equivalent to 880 IU vitamin D3 were administered orally as a maintenance treatment once a day.

RESULTS

The mean age of the patients was 21.7 ± 3.5. After Ca/Vit D supplementation, Vit D levels significantly increased compared to baseline (8.6 ng/ml) levels. An increase in SHBG levels (p < 0.001), a decrease in total testosterone, FAI (p = 0.042), and ADMA levels (p < 0.001) were observed in the first and third months compared to the onset. Significant improvement compared to baseline was observed in menstrual irregularity and median mFG score.

CONCLUSION

Ca/Vit D supplementation can improve PCOS symptoms such as menstrual dysfunction, hirsutism, and hyperandrogenism. It may be effective in reducing the risk of cardiovascular disease in patients with PCOS later in life by decreasing ADMA levels, which is an indicator of endothelial dysfunction.

Mechanisms Involved in the Relationship between Vitamin D and Insulin Resistance: Impact on Clinical Practice

Recent evidence has revealed anti-inflammatory properties of vitamin D as well as extra-skeletal activity. In this context, vitamin D seems to be involved in infections, autoimmune diseases, cardiometabolic diseases, and cancer development. In recent years, the relationship between vitamin D and insulin resistance has been a topic of growing interest. Low 25-hydroxyvitamin D (25(OH)D) levels appear to be associated with most of the insulin resistance disorders described to date. In fact, vitamin D deficiency may be one of the factors accelerating the development of insulin resistance. Vitamin D deficiency is a common problem in the population and may be associated with the pathogenesis of diseases related to insulin resistance, such as obesity, diabetes, metabolic syndrome (MS) and polycystic ovary syndrome (PCOS). An important question is the identification of 25(OH)D levels capable of generating an effect on insulin resistance, glucose metabolism and to decrease the risk of developing insulin resistance related disorders. The benefits of 25(OH)D supplementation/repletion on bone health are well known, and although there is a biological plausibility linking the status of vitamin D and insulin resistance supported by basic and clinical research findings, well-designed randomized clinical trials as well as basic research are necessary to know the molecular pathways involved in this association.

Low vitamin D levels in follicular fluid, but not in serum, are associated with adverse outcomes in assisted reproduction

PURPOSE

To assess the relationship between serum/follicular fluid (FF) vitamin D (VD) status and assisted reproductive technology (ART) treatment outcomes among infertile patients.

METHODS

A prospective cohort study, including 132 infertile patients scheduled for their first ART treatment cycle, was carried out in a Reproductive Medical Center. Serum and FF samples were collected to assess 25-hydroxy VD [25(OH)D] levels. Low VD level was defined as 25(OH)D concentration of less than 30 ng/mL.

RESULTS

Most infertile patients had low VD levels in serum (88%) and FF (90%). We observed a moderately positive correlation between VD levels in serum and FF (r = 0.34, p < 0.0001). Compared to the group of patients with low VD levels in the FF, those with sufficient VD levels had a significantly higher number of retrieved oocytes (p = 0.03), normal fertilization (p = 0.01), and high-quality embryos (p = 0.001). Moreover, patients with sufficient VD levels in the FF also had significantly higher implantation rates than those with low VD levels (76.92% vs. 46.58%, respectively, p = 0.01) and clinical pregnancy rates (92.31% vs. 61.54%, respectively, p = 0.04).

CONCLUSION

These data collectively revealed that low VD levels in serum and FF were common among infertile patients. VD levels in FF, but not in serum, were associated with embryo quality, normal fertilization, implantation rates, and clinical pregnancy rates. Further studies are mandatory to determine the molecular mechanism and VD's potential therapeutic benefits in infertile patients.

Nutrition Strategy and Life Style in Polycystic Ovary Syndrome-Narrative Review

Here we present an extensive narrative review of the broadly understood modifications to the lifestyles of women with polycystic ovary syndrome (PCOS). The PubMed database was analyzed, combining PCOS entries with causes, diseases, diet supplementation, lifestyle, physical activity, and use of herbs. The metabolic pathways leading to disturbances in lipid, carbohydrate, and hormonal metabolism in targeted patients are described. The article refers to sleep disorders, changes in mental health parameters, and causes of oxidative stress and inflammation. These conditions consistently lead to the occurrence of severe diseases in patients suffering from diabetes, the fatty degeneration of internal organs, infertility, atherosclerosis, cardiovascular diseases, dysbiosis, and cancer. The modification of lifestyles, diet patterns and proper selection of nutrients, pharmacological and natural supplementation in the form of herbs, and physical activity have been proposed. The progress and consequences of PCOS are largely modifiable and depend on the patient’s approach, although we have to take into account also the genetic determinants.

Effects of Vitamin D Supplementation on Surrogate Markers of Fertility in PCOS Women: A Randomized Controlled Trial

Vitamin D (VD) might play an important role in polycystic ovary syndrome (PCOS) and female fertility. However, evidence from randomized controlled trials (RCT) is sparse. We examined VD effects on anti-Müllerian hormone (AMH) and other endocrine markers in PCOS and non-PCOS women. This is a post hoc analysis of a single-center, double-blind RCT conducted between December 2011 and October 2017 at the endocrine outpatient clinic at the Medical University of Graz, Austria. We included 180 PCOS women and 150 non-PCOS women with serum 25-hydroxyvitamin D (25(OH)D) concentrations <75 nmol/L in the trial. We randomized subjects to receive 20,000 IU of VD3/week (119 PCOS, 99 non-PCOS women) or placebo (61 PCOS, 51 non-PCOS women) for 24 weeks. Outcome measures were AMH, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, dehydroepiandrosterone sulfate, and androstenedione. In PCOS women, we observed a significant treatment effect on FSH (mean treatment effect 0.94, 95% confidence interval [CI] 0.087 to 1.799, p = 0.031) and LH/FSH ratio (mean treatment effect −0.335, 95% CI −0.621 to 0.050, p = 0.022), whereas no significant effect was observed in non-PCOS women. In PCOS women, VD treatment for 24 weeks had a significant effect on FSH and LH/FSH ratio but no effect on AMH levels.

The efficacy of vitamin D combined with clomiphene citrate in ovulation induction in overweight women with polycystic ovary syndrome: a double blind, randomized clinical trial

PURPOSE

The aim of this study was to assess the effect of vitamin D supplementation on ovulation rate in overweight subfertile women with PCOS undergoing ovulation induction.

METHODS

This was a single center, parallel-groups, double-blind, and placebo-controlled randomized trial involving 186 eligible women undergoing induction of ovulation with clomiphene citrate (Clomid®, Aventis) 50 mg tablet twice daily starting from the third day of menstrual cycle and for 5 days combined with either oral Vitamin D (ossofortin®, EVA PHARMA) 10,000 IU twice weekly and calcium (calciprex®, Marcyrl Pharmaceutical Industries) 1250 mg twice daily or to receive a placebo with calcium for three successive induction cycles. The vitamin D or placebo supplementation started 1 month before induction cycles (total four cycles). Cycles were monitored with ultrasound follicle tracking and mid-luteal serum progesterone measurement. The primary outcome was the ovulation rate after three induction cycles.

RESULTS

The study was performed during the period between January 2018 and September 2018, Eighty six (92.5%) women in the treatment group and 73 (78.5%) in the control group had successful ovulation (p = 0.007). The absolute and relative risk reduction was 14% and 65% respectively. Biochemical and clinical pregnancy occurred in 61.3 and 50.5% in the treatment group, and in 49.5 and 39.8% in the control group (p = 0.105 and 0.141 respectively).

CONCLUSION

In subfertile women with PCOS undergoing induction of ovulation, vitamin D supplementation significantly improved the ovulation rate; however, there was no effect on clinical or biochemical pregnancy.

Effect of vitamin D supplementation on polycystic ovary syndrome: A meta-analysis

The aim of the present meta-analysis was to evaluate the effect of vitamin D supplementation on patients with polycystic ovary syndrome (PCOS). A literature search was performed to identify all of the relevant studies comparing the effect of vitamin D supplementation with placebo in PCOS patients, in the PubMed, Embase and Web of Science databases. All statistical analyses were performed on case-control studies using Review Manager 5.3 software, provided by the Cochrane Collaboration. A total of 11 studies involving 483 participants were included in the current meta-analysis. Vitamin D supplementation appeared to lead to an improvement in the levels of total testosterone [weighted mean differences (WMD) = -0.10, 95% CI (-0.18, -0.02)], homeostasis model assessment of insulin resistance [WMD = -0.44, 95% CI (-0.86, -0.03)], homeostasis model assessment of β-cell function [WMD = -16.65, 95% CI (-19.49, -13.80)], total cholesterol [WMD = -11.90, 95% CI (-15.67, -8.13)] and low-density lipoprotein-cholesterol [WMD = -4.54; 95% CI (-7.29, -1.80)]. The results failed to show a positive effect of vitamin D supplementation on the body mass index, dehydroepiandrosterone sulfate, triglyceride levels or high-density lipoprotein-cholesterol. In conclusion, the data from the available randomized controlled trials (RCTs) suggested vitamin D supplementation reduced insulin resistance and hyperandrogenism, as well improving the lipid metabolism of patients with PCOS to an extent. Further high-quality RCTs from a variety of regions in the world are required to determine the effectiveness of vitamin D supplementation in PCOS patients, and to determine a suitable dose and unit of vitamin D.

Type 2 Diabetes Mellitus, Insulin Resistance, and Vitamin D

PURPOSE OF REVIEW

There is a growing, largely inconsistent, literature on the role of vitamin D in association with type 2 diabetes, insulin resistance/insulin secretion, glycemic indices, and complications of type 2 diabetes. Pathophysiologic, bystander, preventive, and treatment roles of vitamin D have all been proposed. In this focused review, we attempt to organize and clarify our current information in this area.

RECENT FINDINGS

Clinical study interpretation is difficult because of variability in dosage, dosage form, study duration, and populations studied, as well as recently reported normal human polymorphisms in vitamin D synthesis and catabolism, vitamin D-binding protein, and vitamin D receptors in addition to a host of potential epigenetic confounders. Low vitamin D status appears to be associated with type 2 diabetes and most other insulin resistance disorders reported to date. The extraskeletal benefits of supplementation/repletion in these disorders in our species, with a few highlighted exceptions, remain to be established. This focused review attempts to summarize our current knowledge in this burgeoning area through a review of key meta-analyses, observational studies, randomized control trials, and Mendelian randomization studies and will hopefully serve as a guide to indicate future research directions and current best practice.

A Randomized, Controlled Trial of Vitamin D Supplementation on Cardiovascular Risk Factors, Hormones, and Liver Markers in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) increases the risk of metabolic syndrome and non-alcoholic-fatty-liver disease (NAFLD). Vitamin D supplementation may exert positive effects on liver biochemistry in patients with NAFLD; however, its effects on PCOS are unknown. This randomized, double-blind, placebo-controlled study explored the effect of vitamin D supplementation on cardiovascular risk factors (high-sensitivity C-reactive protein (hs-CRP), weight, body mass index (BMI), lipid profile, glucose levels, insulin levels, the homeostatic model assessment-insulin resistance (HOMA-IR), hormones (free androgen index (FAI), testosterone, sex hormone binding globulin (SHBG), and liver markers (alanine aminotransferase (ALT), hyaluronic acid (HA), N-terminal pro-peptide of type III procollagen (PIIINP), tissue inhibitor of metallo-proteinases-1 (TIMP-1), and the enhanced liver fibrosis (ELF) score). Forty women with PCOS were recruited and randomized to vitamin D (3200 IU) or placebo daily for 3 months. All outcomes were measured at baseline and 3 months follow-up (FU). Greater increases in vitamin D levels were shown in the supplementation group (vitamin D, baseline: 25.6 ± 11.4 nmol/L, FU: 90.4 ± 19.5 nmol/L vs. placebo, baseline: 30.9 ± 11.1 nmol/L, FU: 47.6 ± 20.5 nmol/L, p < 0.001). Between groups comparisons (% baseline change) revealed significant differences in ALT (p = 0.042) and a weak effect indicating a greater reduction in the HOMA-IR in the vitamin D group (p = 0.051). No further between group differences were seen in other cardiovascular risk factor, liver markers, or hormones. This study supports beneficial effects of vitamin D supplementation on liver markers and modest improvements in insulin sensitivity in vitamin D deficient women with PCOS.

Genetic polymorphisms of melatonin receptors 1A and 1B may result in disordered lipid metabolism in obese patients with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a condition in which a woman's levels of the sex hormones (estrogen and progesterone) are out of balance, leading to the growth of ovarian cysts. PCOS can affect the menstrual cycle, fertility, cardiac function and even appearance of women. Therefore, we aimed to explore the genetic polymorphism of the melatonin receptors 1A and 1B in obese patients with PCOS to identify a new theoretical basis for its treatment. Patients presenting with PCOS (n=359) were enrolled and classified into an obese OB-PCOS group [body mass index (BMI) of PCOS patients ≥25 kg/m²] or a nonobese NOB-PCOS group, and 215 oviduct infertile patients who experienced normal ovulation were used as the control group. All baseline characteristics, endocrine hormone levels, lipid and glucose metabolism, and insulin indices were measured. The genotypes of rs2119882 within the MTNR1A gene and of rs10830963 within the MTNR1B gene were determined by PCR-RFLP; the genotype frequency and the difference in the distribution of allele frequency were compared. For rs2119882, C allele carriers who were not diagnosed with PCOS had an increased risk of developing PCOS, and C allele carriers with PCOS had an increased risk of developing OB-PCOS. For rs10830963, G allele carriers who were not diagnosed with PCOS had an increased risk of developing PCOS. The TT genotype in rs2119882 and the CC genotype in rs10830963 were protective factors for OB-PCOS, and increased levels of LH, testosterone, and estradiol and abnormal menstruation were key risk factors for PCOS. Furthermore, the TT genotype at the rs2119882 site was the key protective factor for OB-PCOS patients. Our study found that MTNR1A rs2119882 and MTNR1B rs10830963 could increase the risk for PCOS and cause glycolipid metabolism disorder in PCOS patients.

The effects of vitamin D supplementation on metabolic profiles and gene expression of insulin and lipid metabolism in infertile polycystic ovary syndrome candidates for in vitro fertilization

BACKGROUND

Vitamin D deficiency in women diagnosed with polycystic ovary syndrome (PCOS) remarkably decreases the chance of pregnancy, which might be related to its impact on metabolic abnormalities in these patients. It is hypothesized that vitamin D supplementation influences metabolic profile of these patients and indirectly might affect fertility and the outcomes. Therefore, this study was conducted to determine the effects of vitamin D supplementation on the levels of anti-Müllerian hormone (AMH), metabolic profiles, and gene expression of insulin and lipid metabolism in infertile women with PCOS who were candidate for in vitro fertilization (IVF).

METHODS

This study was a randomized, double-blinded, placebo-controlled trial conducted among 40 infertile women, aged 18-40 years, diagnosed with PCOS and was candidate for IVF. Participants were randomly assigned into two intervention groups for receiving either 50,000 IU vitamin D or placebo (n = 20 each group) every other week for 8 weeks. Gene expression for insulin and lipid metabolism was conducted using peripheral blood mononuclear cells (PBMCs) of women with PCOS, via RT-PCR method.

RESULTS

Vitamin D supplementation led to a significant reduction in serum AMH (- 0.7 ± 1.2 vs. - 0.1 ± 0.5 ng/mL, P = 0.02), insulin levels (- 1.4 ± 1.6 vs. -0.3 ± 0.9 μIU/mL, P = 0.007), homeostatic model of assessment for insulin resistance (- 0.3 ± 0.3 vs. -0.1 ± 0.2, P = 0.008), and a significant increase in quantitative insulin sensitivity check index (+ 0.009 ± 0.01 vs. + 0.001 ± 0.004, P = 0.04), compared with the placebo. Moreover, following vitamin D supplementation there was a significant decrease in serum total- (- 5.1 ± 12.6 vs. + 2.9 ± 10.9 mg/dL, P = 0.03) and LDL-cholesterol levels (- 4.5 ± 10.3 vs. + 2.5 ± 10.6 mg/dL, P = 0.04) compared with the placebo.

CONCLUSION

Overall, the findings of this trial supported that 50,000 IU vitamin D supplementation every other week for 8 weeks had beneficial effects on insulin metabolism, and lipid profile of infertile women with PCOS who are candidate for IVF. These benefits might not be evident upon having sufficient vitamin D levels.

TRIAL REGISTRATION

This study was retrospectively registered in the Iranian website ( www.irct.ir ) for clinical trials registration ( http://www.irct.ir : IRCT20170513033941N27).

Vitamin D as a follicular marker of human oocyte quality and a serum marker of in vitro fertilization outcome

PURPOSE

This study investigated the relationship between the vitamin D [25(OH)D] level in individual follicles and oocyte developmental competence.

METHODS

A prospective cohort study in a private infertility center. Infertile women (N = 198) scheduled for intracytoplasmic sperm injection (ICSI) and a single embryo transfer (SET) provided serum samples and 322 follicular fluid (FF) specimens, each from a single follicle on the day of oocyte retrieval.

RESULTS

FFs corresponding to successfully fertilized oocytes (following ICSI) contained significantly lower 25(OH)D level compared with those that were not fertilized (28.4 vs. 34.0 ng/ml, P = 0.001). Top quality embryos on the third day after fertilization, when compared to other available embryos, developed from oocytes collected from follicles containing significantly lower 25(OH)D levels (24.56 vs. 29.59 ng/ml, P = 0.007). Positive hCG, clinical pregnancy, and live birth rates were achieved from embryos derived from oocytes that grew in FF with significantly lower 25(OH)D levels than in follicles not associated with subsequent pregnancy. The concentration of 25(OH)D in FF in women with negative hCG was 32.23 ± 20.21 ng/ml, positive hCG 23.62 ± 6.09 ng/ml, clinical pregnancy 23.13 ± 6.09 ng/ml, and live birth 23.45 ± 6.11 ng/ml (P < 0.001). Women with serum 25(OH)D < 20 ng/ml had not only a higher fertilization rate (71 vs. 61.6%, P = 0.026) and a higher clinical pregnancy rate (48.2 vs. 25%, P = 0.001), but also higher miscarriage rate (14.5 vs. 3.8%, P = 0.013) compared with those with levels ≥ 20 ng/ml.

CONCLUSION

This study reveals that the level of 25(OH)D in FF correlates negatively with the oocytes' ability to undergo fertilization and subsequent preimplantation embryo development. Oocytes matured in FF with low 25(OH)D concentration are more likely to produce top quality embryos and are associated with higher pregnancy and delivery rates. On the other hand, low serum vitamin D concentration is associated with higher miscarriage rates.

Effects of vitamin D supplementation on metabolic and endocrine parameters in PCOS: a randomized-controlled trial

PURPOSE

Vitamin D status may be associated with insulin resistance and other key features of polycystic ovary syndrome (PCOS), but data from preliminary randomized controlled trials (RCTs) are conflicting. Therefore, we aimed to investigate the effects of vitamin D supplementation on plasma glucose area under the curve (AUCgluc, primary outcome measure) and on other metabolic and endocrine parameters (secondary outcome measures).

METHODS

This study was a single-center, double-blind, randomized placebo-controlled trial conducted between December 2011 and July 2017 at the Medical University of Graz, Austria. One-hundred and eighty women with PCOS and 25-hydroxyvitamin D [25(OH)D] concentrations < 75 nmol/L were randomized in a 2:1 ratio to either receive 20,000 IU of cholecalciferol weekly or placebo over 24 weeks. Primary outcome was the between-group difference in AUCgluc at study end while adjusting for baseline values.

RESULTS

In total, 123 participants completed the study [age 25.9 ± 4.7 years; BMI 27.5 ± 7.3 kg/m²; baseline 25(OH)D 48.8 ± 16.9 nmol/L, baseline fasting glucose 84 ± 8 mg/dL]. Vitamin D supplementation lead to a significant increase in 25(OH)D [mean treatment effect 33.4 nmol/L; 95% confidence interval (CI) 24.5 to 42.2; p < 0.001] but had no significant effect on AUCgluc (mean treatment effect - 9.19; 95% CI - 21.40 to 3.02; p = 0.139). Regarding secondary outcome measures, we observed a significant decrease in plasma glucose at 60 min during oral glucose tolerance test (mean treatment effect - 10.2 mg/dL; 95% CI - 20.2 to - 0.3; p = 0.045).

CONCLUSIONS

Vitamin D supplementation had no significant effect on metabolic and endocrine parameters in PCOS with the exception of a reduced plasma glucose during OGTT.

The effect of vitamin D supplementation in combination with low-calorie diet on anthropometric indices and androgen hormones in women with polycystic ovary syndrome: a double-blind, randomized, placebo-controlled trial

PURPOSE

Polycystic ovary syndrome (PCOS) is known as the most common endocrine disorder in reproductive age women. The aim of this studywas to evaluate the effects of vitamin D supplementation in combination with low-calorie diet on anthropometric indices, reproductive hormones and menstrual regularity in overweight and obese PCOS women.

METHODS

In this randomized controlled clinical trial, 60 PCOS women with vitamin D insufficiency were randomly assigned to 12 weeks of either (1) weight-loss intervention + 50,000 IU/week oral vitamin D3 or (2) weight-loss intervention + placebo. At the beginning and end of the study, the anthropometric indices, body composition, 25-hydroxyvitamin D, total testosterone, dehydroepiandrosterone sulfate (DHEAS), sex hormone-binding globulin (SHBG) and free androgen index (FAI) were measured and regularity of menses was compared among the two groups.

RESULT

After 12-week intervention, median of serum 25-hydroxyvitamin D3 significantly increased from 18.5 (10.75-20) ng/ml to 42.69 (34-53.25) ng/ml in vitamin D group compared to placebo group (p < 001). Moreover, there was a significant improvement in frequency regular menstrual cycle (p = 0.01). Mean of weight, body mass index, fat mass, waist and hip circumference and waist-to-hip ratio significantly decreased in both groups, but was not different between two groups. Mean of total testosterone insignificantly decreased from 0.7 to 0.5 ng/ml in vitamin D group (p = 0.18). In addition, we did not observe significant differences regarding DHEAS, FAI and SHBG between two groups.

CONCLUSIONS

In women with PCOS, androgen profile did not change with vitamin D supplementation when combined with low-calorie diet, but menstrual frequency significantly improved.

CLINICAL TRIAL REGISTRATION NUMBER

IRCT2016062710826N19.

Vitamin D, PCOS and androgens in men: a systematic review

BACKGROUND

Accumulating evidence from animal and human studies suggests that vitamin D is involved in many functions of the reproductive system in both genders.

AIM

The aim of this review was to provide an overview on the effects of vitamin D on polycystic ovary syndrome (PCOS) in women and androgen metabolism in men.

METHODS

We performed a systematic literature search in PubMed for relevant English language publications published from January 2012 until September 2017.

RESULTS AND DISCUSSION

The vitamin D receptor and vitamin D-metabolizing enzymes are found in reproductive tissues of women and men. In women, vitamin D status has been associated with several features of PCOS. In detail, cross-sectional data suggest a regulatory role of vitamin D in PCOS-related aspects such as ovulatory dysfunction, insulin resistance as well as hyperandrogenism. Moreover, results from randomized controlled trials (RCTs) suggest that vitamin D supplementation may be beneficial for metabolic, endocrine and fertility aspects in PCOS. In men, vitamin D status has been associated with androgen levels and hypogonadism. Further, there is some evidence for a favorable effect of vitamin D supplementation on testosterone concentrations, although others failed to show a significant effect on testosterone levels.

CONCLUSION

In summary, vitamin D deficiency is associated with adverse fertility outcomes including PCOS and hypogonadism, but the evidence is insufficient to establish causality. High-quality RCTs are needed to further evaluate the effects of vitamin D supplementation in PCOS women as well as on androgen levels in men.

Shedding new light on female fertility: The role of vitamin D

In the last decades several studies suggested that vitamin D is involved in the modulation of the reproductive process in women due to the expression of VDR and 1α-hydroxylase in reproductive tissues such as ovary, uterus, placenta, pituitary and hypothalamus. Vitamin D has also a role in the regulation of sex hormone steroidogenesis. Increasing evidence suggests that vitamin D might have a regulatory role in polycystic ovary syndrome (PCOS)-associated symptoms, including ovulatory dysfunction, insulin resistance and hyperandrogenism. Vitamin D deficiency also has been reported to contribute to the pathogenesis of endometriosis due to its immunomodulatory and anti-inflammatory properties. Although most of the studies supported a role of vitamin D in the onset of these diseases, randomized controlled trials to assess the efficacy of vitamin D supplementation have never been performed. In this review we critically discuss the role of vitamin D in female fertility, starting from in vitro and in vivo studies, focusing our attention on the two most frequent causes of female infertility: PCOS and endometriosis.

Study of Effect of Vitamin D Supplementation on the Clinical, Hormonal and Metabolic Profile of the PCOS Women

INTRODUCTION

Insulin resistance is one of the most common features of polycystic ovary syndrome, and some studies suggest that vitamin D deficiency may have role in insulin resistance.

OBJECTIVE

To study the effect of vitamin D supplementation on the clinical, hormonal and metabolic profile of the PCOS women.

STUDY DESIGN

Randomized, placebo-controlled, interventional, double-blind study.

MATERIALS AND METHODS

PCOS women were evaluated and enrolled after considering inclusion and exclusion criteria. They were randomized by block randomization with sealed envelope system done in two groups. In the study group (n = 25), patients were supplemented with vitamin D 60,000 IU weekly for 12 weeks, whereas control group (n = 25) was given placebo weekly for the same period. Both the groups were compared pre- and post-supplementation for variables like clinical profile, biochemical profile and metabolic profile. Statistical analysis was performed by the SPSS program for Windows, version 10.1 (SPSS, Chicago, IL).

RESULT

In the study (n = 50), PCOS patients were enrolled; 34 patients (68%) were vitamin D deficient (≤20 ng/ml) out of which 10 patients (29%) were severely deficient (<10 ng/ml). Twelve patients (24%) were vitamin D insufficient showing high prevalence of vitamin D deficiency in the PCOS women. The difference in mean serum fasting glucose pre- and post-supplementation of vitamin D in study group was found to be statistically significant with p value of 0.041. There was significant difference seen in insulin resistance (IR) (2.38 ± 4.88-1.00 ± 0.58, p = 0.003), serum fasting insulin (10.34 ± 20.00-5.00 ± 3.25, p = 0.021), and increase in insulin sensitivity determined by QUICKI (0.37 ± 0.04-0.394 ± 0.009, p = 0.001) after supplementation with vitamin D.

CONCLUSION

The study concluded that there was a beneficial effect of vitamin D supplementation on ovulatory dysfunctions and blood pressure. Post-supplementation, there were decrease in insulin resistance and increase in insulin sensitivity. In the study decreased serum fasting insulin level and fasting blood sugar after vitamin D supplementation suggest underlying role of vitamin D in glucose homeostasis.

Correlation of Vitamin D with metabolic parameters in polycystic ovarian syndrome

BACKGROUND

Polycystic ovarian syndrome (PCOS) and hypovitaminosis D are the two most common endocrine disorders in young women leading to many adverse metabolic consequences. We evaluated the correlation of 25-hydroxy Vitamin D (25OHD) with metabolic parameters and insulin resistance in PCOS.

MATERIALS AND METHODS

We included 100 PCOS patients (age 18-40 years, duration >6 months) serially, in this cross-sectional study. We excluded patients with past use of insulin sensitizers and hormone therapy. All patients underwent a physical examination, body fat estimation, and a single fasting blood sample was analyzed for the biochemical parameters. The patients were divided into 2 groups as per the 25OHD level: Group 1 (Deficient, <30 ng/mL) and Group 2 (normal). The data were analyzed using appropriate statistical methods, and a P < 0.05 was considered statistically significant.

RESULTS

The study population had a mean age of 28.6 ± 6.3 years, body mass index (BMI) 30.4 ± 6.1 kg/m² and body fat of 39.1 ± 13%. A total of 90 women had 25OHD deficiency, and hypovitaminosis D was observed more in younger, obese patients. Patients with hypovitaminosis D had a higher BMI (P = 0.0124), low- high-density lipoprotein (P = 0.0094), calcium (P ≤ 0.0001), and elevated testosterone (P = 0.0412) in comparison with normal 25OHD patients. None of the metabolic parameters showed significant correlation with 25OHD (P > 0.05).

CONCLUSION

Hypovitaminosis D is very common in PCOS patients and exacerbates the metabolic abnormalities. It is essential to screen all the PCOS patients for 25OHD deficiency, and further large-scale studies are required to confirm our findings.

Effects of vitamin D supplementation on metabolic indices and hs-CRP levels in gestational diabetes mellitus patients: a randomized, double-blinded, placebo-controlled clinical trial

BACKGROUND/OBJECTIVES

Vitamin D plays an important role in the etiology of gestational diabetes mellitus (GDM). This study evaluated the effect of vitamin D supplementation on metabolic indices and hs-C-reactive protein (CRP) levels in GDM patients.

SUBJECTS/METHODS

The study was a randomized, placebo-controlled, double-blinded clinical trial. Seventy-six pregnant women with GDM and gestational age between 24-28 weeks were assigned to receive four oral treatments consisting of 50,000 IU of vitamin D3 (n = 38) or placebo (n = 38) once every 2 weeks for 2 months. Fasting blood glucose (FG), insulin, HbA1c, 25-hydroxyvitamin D, lipid profile, hs-CRP, and homeostasis model assessment-insulin resistance (HOMA-IR) were measured before and after treatment. Independent and paired t-tests were used to determine intra- and intergroup differences, respectively. ANCOVA was used to assess the effects of vitamin D supplementation on biochemical parameters.

RESULTS

Compared with the placebo group, in the vitamin D group, the serum level of 25-hydroxyvitamin D increased (19.15 vs. -0.40 ng/ml; P < 0.01) and that of FG (-4.72 vs. 5.27 mg/dl; P = 0.01) as well as HbA1c (-0.18% vs. 0.17%; P = 0.02) decreased. Improvements in the lipid profiles were observed in the vitamin D group, but without statistical significance. Significant increases in concentrations of hs-CRP, FG, HbA1c, total cholesterol, and LDL cholesterol were observed in the placebo group. No significant change in fasting insulin and HOMA-IR was observed in either group.

CONCLUSIONS

In GDM patients, vitamin D supplementation improved FG and HbA1c but had no significant effects on lipid profile or hs-CRP.

Hypovitaminosis D and Associated Cardiometabolic Risk in Women with PCOS

INTRODUCTION

Women with Polycystic Ovary Syndrome (PCOS) frequently suffer from metabolic disturbances like insulin resistance, hypertension and atherogenic dyslipidemia. Accumulating evidences suggest that Vitamin D deficiency is common in PCOS and may be associated with metabolic and endocrinal dysfunctions in PCOS. Thus women with PCOS may be at elevated risk of cardiovascular disease.

AIM

Present study aims to evaluate Vitamin D status and to assess its association with metabolic and endocrinal dysregulations in women with PCOS, which might help in early identification and prevention of future symptomatic cardiac disease.

MATERIALS AND METHODS

A total of 44 women with PCOS, diagnosed by Rotterdam criteria and 45 healthy control without PCOS, were evaluated for Vitamin D and cardiometabolic risk factors, including fasting plasma glucose, insulin resistance, dyslipidemia, hs-CRP. That apart, several endocrinal parameters of hyperandrogenism were also examined. Several correlation studies were determined to establish the role of Vitamin D as a cardiometabolic risk factor in PCOS.

RESULTS

Results were expressed as mean±SD and were statistically analysed using SPSS software version 16, unpaired student's t-test and Pearson's correlation coefficient. We found lower levels of Vitamin D, which was statistically significant as compared to healthy controls. Hyperinsulinemia, rise in insulin resistance and marked dyslipidemia was observed in the present study. Another relevant finding was significant correlation of Vitamin D with insulin and Homeostatic Model of Assessment- Insulin Resistance Index (HOMA-IR).

CONCLUSION

Hypovitaminosis D was prevalent in PCOS. This was related to metabolic and hormonal disorders in PCOS. Possibly this combined with impaired fasting glucose, IR and dyslipidemia, could account for Cardio vascular risks in PCOS. Further prospective observational studies and randomized control trials are required to explore the above hypothesis.

Serum Vitamin D Levels and Polycystic Ovary syndrome: A Systematic Review and Meta-Analysis

Vitamin D deficiency (VDD) is common in women with and without polycystic ovary syndrome (PCOS) and may be associated with metabolic and endocrine disorders in PCOS. The aim of this meta-analysis is to assess the associations of serum vitamin D levels with metabolic and endocrine dysregulations in women with PCOS, and to determine effects of vitamin D supplementation on metabolic and hormonal functions in PCOS patients. The literature search was undertaken through five databases until 16 January 2015 for both observational and experimental studies concerning relationships between vitamin D and PCOS. A total of 366 citations were identified, of which 30 were selected (n = 3182). We found that lower serum vitamin D levels were related to metabolic and hormonal disorders in women with PCOS. Specifically, PCOS patients with VDD were more likely to have dysglycemia (e.g., increased levels of fasting glucose and homeostatic model assessment-insulin resistance index (HOMA-IR)) compared to those without VDD. This meta-analysis found no evidence that vitamin D supplementation reduced or mitigated metabolic and hormonal dysregulations in PCOS. VDD may be a comorbid manifestation of PCOS or a minor pathway in PCOS associated metabolic and hormonal dysregulation. Future prospective observational studies and randomized controlled trials with repeated VDD assessment and better characterization of PCOS disease severity at enrollment are needed to clarify whether VDD is a co-determinant of hormonal and metabolic dysregulations in PCOS, represents a consequence of hormonal and metabolic dysregulations in PCOS or both.

Effect of vitamin D supplementation on insulin kinetics and cardiovascular risk factors in polycystic ovarian syndrome: a pilot study

To assess the effect of vitamin D supplementation on parameters of insulin sensitivity/resistance (IS/IR) and insulin secretion in subjects with polycystic ovarian syndrome (PCOS). A prospective double-blind randomized control trial was conducted to assess the effect of vitamin D on insulin kinetics in women with PCOS. The trial was conducted in a tertiary care research hospital. A total of 36 subjects with PCOS, aged 18-35 years, were included in this study. Vitamin D3 4000 IU/day versus placebo was given once a month for 6 months and both groups received metformin. IS (by whole-body IS index or Matsuda index), IR (by homeostasis model assessment IR (HOMA-IR)), and insulin secretion (by insulinogenic index; II30) were the main outcome measures. Secondary outcome included blood pressure (BP), lipid profile, disposition index (DI), and vascular stiffness. Out of 36 subjects who consented, 32 completed the study. Subjects were randomized into two groups: group A (n=15; metformin and vitamin D 4000 IU/day) or group B (n=17; metformin and placebo). Oral glucose tolerance tests with 75 g glucose were carried out at baseline and 6 months after supplementation. Hypovitaminosis D was observed in 93.8% of all subjects with mean serum 25 hydroxy vitamin D level of 7.30±4.45 ng/ml. After 6 months of vitamin D supplementation, there was no significant difference in any of the parameters of IS/IR (area under curve (AUC)-glucose, AUC-insulin, insulin:glucose ratio, HOMA-IR, Matsuda index, insulinogenic index, and DI), II30, and cardiovascular risk factors between the two groups. Supplementation of vitamin D, at a dose of 4000 IU/day for 6 months, did not have any significant effect on parameters of IS/IR and insulin secretion in subjects with PCOS.

The pleiotropic effects of vitamin D in gynaecological and obstetric diseases: an overview on a hot topic

The traditionally recognized role of vitamin D consists in the regulation of bone metabolism and calcium-phosphorus homeostasis but recently a lot of in vitro and in vivo studies recognized several “noncalcemic” effects of vitamin D metabolites. Accumulating evidence suggests that the metabolic pathways of this vitamin may play a key role in the developing of gynaecological/obstetric diseases. VDR-mediated signalling pathways and vitamin D levels seem to (deeply) affect the risk of several gynaecological diseases, such as polycystic ovary syndrome (PCOS), endometriosis, and ovarian and even breast cancer. On the other hand, since also the maternal-fetal unit is under the influence of vitamin D, a breakdown in its homeostasis may underlie infertility, preeclampsia, and gestational diabetes mellitus (GDM). According to our literature review, the relationship between vitamin D and gynaecological/obstetric diseases must be replicated in future studies which could clarify the molecular machineries behind their development. We suggest that further investigation should take into account the different serum levels of this vitamin, the several actions which arise from the binding between it and its receptor (taking into account its possible polymorphism), and finally the interplay between vitamin D metabolism and other hormonal and metabolic pathways.

The relationship between Polycystic ovary syndrome and vitamin D levels

Objective:

The main aim of this study was to determine the association of serum 25-hydroxyvitamin D (25-OH D) levels with hormonal, clinical and metabolic profile in patients with and without Polycystic ovary syndrome (PCOS).

Materials and Methods:

Forty-eight normal-weight (body mass index (BMI) of 19-24.99 kg/m²) women with PCOS, 36 overweight (BMI of 25-29.9 kg/m²) women with PCOS and 56 normal-weight controls participated in the study. Blood samples were collected in the early follicular phase (between day 2 and day 5 of the menstrual cycle) at 9:00 am after an overnight fast. Circulating concentrations of 25-OH D, luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, TSH, free testosterone, dehydroepiandrosterone sulphate (DHEA-SO4), 17-hydroxyprogesterone, sex hormone-binding globulin (SHBG), fasting insulin, fasting glucose, and lipid profile were assessed.

Results:

Normal weight (BMI 19-24.99 kg/m²) and overweight (BMI 25-29.99 kg/m²) women with PCOS were compared with normal-weight controls and lower 25-OH D levels were found in both PCOS groups (p<0.05 and p<0.01, respectively 25-OH D significantly negatively correlated with waist circumference (WC), waist-to-hip ratio (WHR), free testosterone and modified Ferriman-Gallwey scores, however, there was a positive correlation between 25-OH D and SHBG levels (p<0.05).

Conclusion:

Our findings suggest that PCOS is associated with hypovitaminosis D.

Vitamin D deficiency in women with polycystic ovary syndrome

Objective

To investigate: the prevalence of vitamin D deficiency in Korean women with polycystic ovary syndrome (PCOS), and the relationship between vitamin D status and clinical or metabolic features in this group.

Methods

We recruited 38 women with PCOS using the Rotterdam criteria. A total of 109 premenopausal control women were matched with patients based on age and body mass index. Serum 25-hydroxy vitamin D concentrations less than 20 ng/mL were classified as frank vitamin D deficiency. Since vitamin D may play a significant role in metabolic disturbances in women with PCOS, correlations between clinical or metabolic parameters and vitamin D status were analyzed separately in patients and controls.

Results

Women with PCOS showed no differences in the level of 25-hydroxy vitamin D (19.6±6.6 ng/mL in patients vs. 20.1±7.4 ng/mL in controls, respectively, p=0.696) or prevalence of vitamin D deficiency (57.9% in patients vs. 56.5% in controls, respectively, p=0.880). In addition, we did not find any correlations between serum vitamin D level and clinical or metabolic profiles in either PCOS patients or controls.

Conclusion

Our study found no differences in the absolute level of serum vitamin D between PCOS patients and matched controls. Prevalence of vitamin D deficiency was equally common among both patients and controls. Additionally, we did not find any correlations between serum vitamin D level and clinical or metabolic profiles, suggesting that the role of vitamin D in the pathogenesis of PCOS is not yet clear.

Vitamin D and assisted reproduction technologies: current concepts

Accumulating evidence from animal and human studies suggests that vitamin D is involved in many functions of the human reproductive system in both genders, but no comprehensive analysis of the potential relationship between vitamin D status and Assisted Reproduction Technologies (ART) outcomes is currently available. On this basis, the purpose of this systematic review and meta-analysis was to perform an in-depth evaluation of clinical studies assessing whether vitamin D status of patients undergoing ART could be related to cycle outcome variables. This issue is of interest considering that vitamin D deficiency is easily amenable to correction and oral vitamin D supplementation is cheap and without significant side effects. Surprisingly, no studies are currently available assessing vitamin D status among male partners of couples undergoing ART, while seven studies on vitamin D status of women undergoing controlled ovarian hyperstimulation (COH) for ART were found and included in the review. Results show that vitamin D deficiency is highly prevalent among women undergoing COH, ranging from 21% to 31% across studies conducted in Western countries and reaching 75-99% in Iranian studies. Data on vitamin D deficiency (25-hydroxyvitamin D serum levels <20 ng/ml) in relation to ART outcomes could be extracted from three studies and included in the meta-analysis, yielding a common risk ratio (RR) of 0.89 (95% CI 0.53-1.49) and showing a lower but not statistically significant likelihood of clinical pregnancy for vitamin-D-deficient women compared with vitamin-D-sufficient patients. In conclusion, there is insufficient evidence to support the routine assessment of vitamin D status to predict the clinical pregnancy rate in couples undergoing ART. The partly conflicting results of the available studies, potentially explaining the lack of statistical significance for a negative influence of vitamin D deficiency on clinical pregnancy rate, are likely secondary to confounders and insufficient sample size, and further larger cohort and randomised controlled studies are required.

High-dose vitamin D supplementation and measures of insulin sensitivity in polycystic ovary syndrome: a randomized, controlled pilot trial

OBJECTIVE

To determine the effects of high-dose vitamin D on insulin sensitivity in polycystic ovary syndrome (PCOS).

DESIGN

Randomized, placebo-controlled trial.

SETTING

Academic medical center.

PATIENT(S)

Twenty-eight women with PCOS.

INTERVENTION(S)

Vitamin D3, 12,000 IU, or placebo daily for 12 weeks.

MAIN OUTCOME MEASURE(S)

The primary outcome was quantitative insulin sensitivity check index. Secondary outcomes included glucose and insulin levels during a 75-g oral glucose tolerance test and blood pressure.

RESULT(S)

Twenty-two women completed the study. Compared with placebo, vitamin D significantly increased 25-hydroxyvitamin D (mean [95% confidence interval] in vitamin D group 20.1 [15.7 to 24.5] ng/mL at baseline and 65.7 [52.3 to 79.2] ng/mL at 12 weeks; placebo 22.5 [18.1 to 26.8] ng/mL at baseline and 23.8 [10.4 to 37.2] ng/mL at 12 weeks). There were no significant differences in quantitative insulin sensitivity check index and other measures of insulin sensitivity; however, we observed trends toward lower 2-hour insulin and lower 2-hour glucose. We also observed a protective effect of vitamin D on blood pressure.

CONCLUSION(S)

In women with PCOS, insulin sensitivity was unchanged with high-dose vitamin D, but there was a trend toward decreased 2-hour insulin and a protective effect on blood pressure.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00907153.

Effects of vitamin D on cardiovascular disease risk factors in polycystic ovary syndrome women with vitamin D deficiency

BACKGROUND

Vitamin D deficiency is prevalent among women, including patients with polycystic ovary syndrome (PCOS). Some studies have suggested that vitamin D may have a role in cardiovascular disease (CVD). There is very limited data on the vitamin D effect on CVD risk factors in women with PCOS and vitamin D deficiency.

AIM

To investigate the effect of cholecalciferol on CVD risk factors in PCOS women with vitamin D deficiency.

METHODS

The study was a randomized, placebo-controlled, double blinded trial. Fifty PCOS women with vitamin D deficiency (vitamin D, no. = 24; placebo, no. = 26) aged 20-40 yr, were randomly assigned to receive 3 oral capsules of 50,000 IU vitamin D3 or a placebo (one capsule every 20 days) for two months. Serum vitamin D, PTH, lipid profile, apolipoprotein AI (APO-AI), and high sensitive C- reactive protein (hs-CRP) were measured at baseline and after treatment.

RESULTS

Vitamin D3 therapy in PCOS patients, increased serum vitamin D (7.00 ± 2.80 to 22.9 ± 6.14 ng/ml), decreased serum total cholesterol (196.6 ± 32.8 to 179.1 ± 34.1 mg/dl), triglyceride (156.8 ± 73.0 to 130.5 ± 56.5 mg/dl), and VLDL (31.4 ± 14.6 to 26.1 ± 11.3 mg/dl) levels significantly (p < 0.05), but it did not affect serum HDL-cholesterol, LDL-cholesterol, APO-AI, and hs-CRP concentrations. There was no change in variables in the placebo group.

CONCLUSIONS

Our study showed that vitamin D3 therapy had beneficial effects on some CVD risk factors in PCOS patients with vitamin D deficiency. The trial was registered at IRCT.ir (IRCT138904113140N2).

Medical management of metabolic dysfunction in PCOS

Polycystic ovary syndrome (PCOS) is associated with metabolic derangements including insulin resistance, dyslipidemia, systemic inflammation and endothelial dysfunction. There is a growing need to develop pharmacologic interventions to improve metabolic function in women with PCOS. Medications that have been tested in patients with PCOS include metformin, thiazolidinediones, acarbose, naltrexone, orlistat, vitamin D and statins. Metformin decreases hepatic gluconeogenesis and free fatty acid oxidation while increasing peripheral glucose uptake. Early studies in PCOS suggested that metformin indirectly reduces insulin level, dyslipidemia and systemic inflammation; however, recent placebo-controlled trials failed to demonstrate significant metabolic benefit. Thiazolidinediones act primarily by increasing peripheral glucose uptake. Most studies in PCOS have demonstrated that thiazolidinediones reduce insulin resistance; however, effects on dyslipidemia were disappointing. Use of thiazolidinediones is associated with weight gain and major complications. Acarbose reduces digestion of polysaccharides. Studies in PCOS yielded inconsistent effects of acarbose on insulin sensitivity and no significant improvement of dyslipidemia. Naltrexone reduces appetite and modulates insulin release; its use in PCOS may reduce hyperinsulinemia. Orlistat decreases absorption of dietary fats; studies in PCOS suggest beneficial effects on insulin sensitivity. Vitamin D may improve insulin sensitivity but mixed results on lipid profile in PCOS have been reported. Statins are competitive inhibitors of the key enzyme regulating the mevalonate pathway; their effects are related to reduced cholesterol production as well as anti-inflammatory and anti-oxidant properties. In women with PCOS, statins reduce hyperandrogenism, improve lipid profile and reduce systemic inflammation while the effects on insulin sensitivity are variable. Use of statins is contraindicated in pregnancy.

Vitamin D - roles in women's reproductive health?

In the past few years a growing interest in vitamin D can be observed in the lay and biomedical literature due to findings demonstrating a low vitamin D status in the population. In addition to its importance for the regulation of calcium and phosphorus homeostasis recent epidemiologic studies have observed relationships between low vitamin D levels and multiple disease states. This secosteroid hormone also regulates the expression of a large number of genes in reproductive tissues implicating a role for vitamin D in female reproduction. In this report we summarize the recent evidence that vitamin D status influences female reproductive and pregnancy outcomes. Human and animal data suggest that low vitamin D status is associated with impaired fertility, endometriosis and polycystic ovary syndrome. Evidence from observational studies shows higher rates of preeclampsia, preterm birth, bacterial vaginosis and gestational diabetes in women with low vitamin D levels. However, confirmation of experimental observations establishing an association of vitamin D deficiency with adverse reproductive outcomes by high quality observational and large-scale randomized clinical trials is still lacking. The determination of optimal 25(OH)D3 levels in the reproductive period and the amount of vitamin D supplementation required to achieve those levels for the numerous actions of vitamin D throughout a woman's life would have important public health implications.